In a preceding Letter [1]} we have reported that the Collins diffraction
formula in cylindrical coordinates is just the transformation matrix element
of a three-parameter (\(k\)  and \(t\)  are complex and satisfy the unimodularity
condition \(kk^{\ast }-tt^{\ast }=1)\)  two-mode squeezing operator [2]}, [3]}
\(F^{\left( t,k\right) }=\exp \left( \frac{t}{k^{\ast }}a_{1}^{\dagger }a_{2}^{\dagger }\right) \exp \left[ \left( a_{1}^{\dagger }a_{1}+a_{2}^{\dagger }a_{2}+1\right) \ln \left( k^{\ast }\right) ^{-1}\right] \exp \left( -\frac{t^{\ast }}{k^{\ast }}a_{1}a_{2}\right) ,\) 
